In a bobbin core holder for vertical creel rods as known from a catalogue "Creels and Bobbin Holders" of ROJ-Electrotex, Italy, (p. I3, I5), the bearing block is not provided radially at the outer periphery of the ring socket. The recess is formed as a blind bore with a bore axis oriented approximately radially towards the axis of the holder. A fixing screw serves to secure the bobbin core when inserted into the recess. This fixing screw is inserted approximately tangentially in relation to the periphery of the ring socket. The bearing block of the known holder protrudes with a considerable extension. Only a relatively short support length for the bobbin core can be achieved. Furthermore, in some cases the bobbin core cannot be inserted far enough into the recess in order to secure a bobbin optimally. With heavy bobbins, locally concentrated loads may occur which leads to premature wearing of the recess, high stresses in the transition from the bearing block to the ring socket, and a vibrating bobbin. In order to change bobbins, the ring socket can be swivelled sidewardly against the holding action of a spring detent mechanism and in relation to the sleeve body. However, the holder allows only one position of the bobbin core, which position is determined by the position of the holder on the creel rod.
From the same catalogue, p. I2 and I5, however a bobbin core holder for horizontal creel rods is known, the recess bore of which is provided in a bearing block which projects sidewardly from the ring socket and is open at both ends, so that the bobbin core can be inserted into the recess bore from one side or the other. The ring socket is rotatable with little force in one direction starting from the working position assured on the fixed holder by the weight of the bobbin (bobbin change). In order to position the bobbin core at the other side of the creel rod, it is necessary to completely release the holder on its creel rod and to rotate it. Furthermore, it is disadvantageous that the bobbin core is held between two clamping flanges by means of two clamping screws. This necessitates cumbersome and time consuming manipulations for securing and releasing the bobbin core and leads to deformations of the clamping flanges thus reducing the useful life thereof. Finally, the sideward distance of the bobbin core from the creel rod is relatively large so that with heavy bobbins, large loads and eccentrical forces occur which deteriorate the holding effect of the holder on the creel rod and produce wear in the material of the holder. The relatively large distance between the bobbin core and the axis of the creel rod cannot prevent vibrations of the bobbin.
It is an object of the invention to create a bobbin core holder which may be utilized with both horizontal and vertical creel rods, and which allows a rapid sidewards pivoting of the bobbin for a bobbin change without need for releasing fastening means. The bobbin core holder in accordance with the invention has compact dimensions and which permits stable and space saving support of the bobbin core. The holder should allow positioning of a bobbin core without cumbersome manipulations either at one side or the other of a creel rod in order to easily cope with restricted mounting space relationships or to provide an optimal yarn withdrawal geometry.
The above object can be achieved by providing the bearing block with a circumferentially closed bore which is open at both ends and has a bore axis oriented laterally relative to the axis of the ring socket. Further, the bore of the bearing block has an intermediate longitudinal section which partially penetrates the ring socket.
The holder is compact, comfortable to manipulate and provides a particularly stable and space saving support for the bobbin core at each creel rod. The bore utilizes space within the "material" of the ring socket and therefore is optimally located close to the creel rod. The bearing block projects outwardly only a small amount. The bobbin core is supported close to the creel rod. The holder is useful for both vertical and horizontal creel rods. The short lever arm of the long bore in relation to the axis of the ring socket not only saves space, but also provides stable support to the mass of the bobbin in case of or against vibrations.
The bore is extremely long with its end sections leaving the ring socket in the bearing block. In this regard, the longitudinal extension of the bore approximately equals the outer diameter of the ring socket. In addition, a threaded bore is oriented generally radially relative to the ring socket axis for receiving a fixing or set screw. As a consequence, significant support length can be achieved for the bobbin core. The bore, being open at both ends, allows the insertion of the bobbin core or the foot part of the bobbin core, respectively, as far as is necessary and suitable for optimum and stable support of the bobbin. Occasionally, the free end of the bobbin core even can project beyond the other bore end. The bobbin core can be introduced into each end of the bore so that the ring socket can be rotated by 180.degree. in order to support the bobbin core at the other side of the creel rod, in case that space restrictions or the yarn geometry could make this necessary. The fixing screw is comfortable to manipulate since it is easily accessible. The rotatability of the ring socket and the spring detent mechanism have a double function since they allow comfortable handling in case of a bobbin exchange as only the ring socket has to be rotated sufficiently far from its working position, and further allow rotation of the ring socket by 180.degree. in order to position the bobbin core at the other side of the creel rod.
The embodiment wherein the threaded bore is provided within a projection of the bearing block is advantageous since the projection of the bearing block assures sufficient material for the fixing screw in its threaded bore without significantly enlarging the compact dimensions of the holder.
In accordance with one embodiment, the threaded bore is embodied by a threaded insert. This embodiment is advantageous since even after an extended period of use wearing of the thread will not occur.
The embodiment wherein the spring detent mechanism is engageable in two rotational positions of the ring socket leads to the advantage that the ring socket has two diametrically opposite and stable rotational positions in which the bobbin core is firmly supported. As a consequence, the bobbin core can be displaced from one side of a creel rod to the other side thereof without releasing the holding action, e.g. in case that the space restriction or the yarn geometry should make this necessary.
An advantageous embodiment which is easy to manufacture and to assemble includes a sleeve body having a pair of detent recesses each for positioning a roller body, and a C-shaped, pre-loaded spring which applies pressure to the roller bodies from the outside. The spring detent mechanism can easily be integrated within the compact dimensions of the ring socket and the sleeve body. With a C-shaped spring, strong holding forces for stable rotational positions of the ring socket can be achieved as soon as the roller bodies engage within the detent recesses.
A particularly stabilized fixing of the holder at its creel rod is possible with the embodiment wherein the sleeve body projects axially beyond both ends of the ring socket and carries annular caps thereon. Furthermore, the caps and the fixation of the caps and of the sleeve body at the creel rod is practical in terms of manufacturing and assembly.
The embodiment wherein the bore and the bearing block are oriented generally perpendicular to the axial direction of the holder serves to secure a bobbin core vertically in relation to the axis of the creel rod.
The embodiments wherein the ring socket and sleeve body are formed of fiber-reinforced plastic material and wherein the caps are formed of metal are advantageous in terms of easy manufacturing and long life duration and low weight.